中文摘要：

为探究土壤团聚体中土壤养分及酶活性的分布特征,以喀斯特地区不同土地利用方式下的灌木林地、皇竹草地、狼尾草地、花椒林地及荒草地土壤为研究对象,研究团聚体中各粒级土壤养分及酶活性的含量,分析了土壤养分与团聚体酶活性之间的相关关系.结果表明：5种不同土地利用方式下土壤养分含量在〈0.25 mm粒级均最高,脲酶及蔗糖酶活性表现为灌木林地〉皇竹草地〉狼尾草地〉花椒林地〉荒草地,碱性磷酸酶表现为花椒林地〉灌木林地〉皇竹草地〉狼尾草地〉荒草地;酶活性随着土壤粒级的减小逐渐增大.将团聚体的含量、养分及酶活性结合考虑,发现2—1 mm粒级团聚体中的养分含量和酶活性对土壤的贡献率最大,土壤团聚体脲酶、蔗糖酶及碱性磷酸酶均与土壤养分呈显著或极显著正相关.说明酶活性可作为土壤肥力的指标之一,且充分显示了土壤性质在不同土地利用方式下及不同粒级中的多样性.

英文摘要：

In order to explore the characteristics of nutrient and enzyme activies distribution in soil aggregates,soil samples from different land use patterns： Shrub land,Pennisetum sinese Roxb,Pennisetum alopecuroides（L.） Spreng. Zanthoxylum and Abandoned grassland in karst area were studied,and the relationship between soil nutrient and agglutinase activity was also analyzed. The results showed that the soil nutrient content was the highest at the 〈 0. 25 mm aggregate,and the activities of urease and invertase were in the order of Shrub forest 〉 Pennisetum sinese Roxb 〉Pennisetum alopecuroides（L.） Spreng. 〉 Zanthoxylum〉 Abandoned grassland; Alkaline phosphatase of Zanthoxylum 〉Shrub forest〉 Pennisetum sinese Roxb〉 Pennisetum alopecuroides（L.） Spreng. 〉Abandoned grassland; We observed that alkaline phosphatase activity increased with decreasing of soil aggregate size. The results also showed that the in 2—1 mm aggregate contributed the highest nutrient content and enzyme activity to the bulk soil. In addition,enzyme activities including sucrase and alkaline phosphatase were all correlated with nutrient status in soil aggregates,which indicating that enzyme activity can be used as one of the indicators of soil fertility,and the diversity of soil properties in different land use patterns and soil aggregates.